The present invention relates to fasteners for attaching masonry walls to stud supports in buildings and other structures. More particularly, the invention provides a fastener which has one end that threads into a wall stud and an opposite end which is anchored to the masonry wall by means of a bonding agent. While the fastener of the invention may be used in various situations, it is most commonly used with structures which require additional stabilization or reinforcement, either due to insufficient reinforcement during initial construction or for seismic reinforcement.
To extend the useful life of a masonry wall, it is commonly anchored to a studded non-masonry wall for support. In order to provide both a moisture barrier between the walls and increase the thermal insulation of the building, the masonry wall is usually separated from the studded wall by an air gap. The width of the air gap typically varies from building to building and, often in older buildings, the air gap width increases due to age and stress.
Conventional fasteners used to anchor masonry walls pass through a bored hole in the masonry wall and traverse the air gap, to either screw into a hole in the stud, or to attach to a bored hole in the stud with an expansion plug. The fasteners are then anchored to the bored hole in the masonry wall with either another expansion plug or with epoxy resin.
Fasteners utilizing expansion plugs are relatively expensive and often result in weak non-uniform anchors. In addition, expansion plugs do not provide water tight seals, thereby requiring additional steps to seal exposed plugs or requiring the installation an O-ring around the fastener and in the air gap to prevent moisture from traveling along the fastener to the internal wall. Somewhat more conventional fasteners of the type disclosed in Anderson U.S. Pat. No. 5,030,052 can be anchored to the masonry wall with a bonding agent, but require numerous time consuming operations and are not readily adapted to variations in air gap width.